1. Field of the Invention
The present invention relates generally to a fiber optic adapter and mating dissimilar multi-fiber connectors, and more particularly, to a fiber optic adapter that allows a TIA FOCIS 5 compliant MTP connector to mate with a dissimilar connector having a pocket at least large enough to accept the FOCIS 5 compliant MTP connector.
2. Technical Background
It is often necessary within fiber optic networks to optically connect optical fibers through mating connectors. Mating connectors may include connector alignment features on the ferrules themselves for fine alignment, but are typically grossly aligned using some form of adapter assembly. Adapters may be stand-alone components or may be maintained within network structures, walls or receptacles, such as within a network connection terminal. While certain like connectors may be mated using known adapter designs, mating dissimilar connectors requires a new, more complex adapter design. Desirable adapters should not only properly align mating connectors, but should also protect the mating connectors and optical fibers from adverse environmental and mechanical influences, such as from side loading, rotational and tensile forces.
Referring to FIG. 1, an example of a conventional multi-fiber optical connector known as a TIA FOCIS 5 compliant MTP® connector (hereinafter referred to as the “MTP connector 20”) is shown. The MTP connector 20 has a generally rectangular cross-section and includes a multi-fiber ferrule 22 maintained within a connector housing 24. The connector housing 24 includes a ferrule surround portion 26 positioned about ferrule 22 and a rear housing portion 28 engaged with the ferrule surround portion 26 and defining a gripping surface 30. The MTP connector 20 further includes a protruding exclusion feature 32 (the exclusion feature 32 may also be referred to as a “key” in some applications) that allows connector insertion into only an appropriate receiver, adapter or connector. The ferrule surround portion 26 protrudes about as far as the end face of the ferrule 22. The ferrule 22 defines guide pin bores 34 and fiber bores 36 for receiving guide pins and optical fibers therein, respectively. The MTP connector 20 may further include a biasing spring and additional components.
Referring to FIG. 2, an example of a conventional multi-fiber optical connector 40 known under the marks “OptiTip™” and “Con2r™” available from Corning Cable Systems of Hickory, N.C. is shown. The connector 40 includes a multi-fiber ferrule 42 maintained within a plug housing 44 defining a key slot 46 for ensuring proper mating and mating orientation. A threaded coupling nut 48 is positioned about the plug housing 44 and threadably engages an adapter or other structure to which the plug 40 is engaged. The plug housing 44 defines an internal cavity 50 having a predetermined geometry that may be defined by the plug housing 44 or by an insert received within the plug housing 44.
Referring to FIG. 3, an attempted mating or connection of the MTP connector 20 shown in FIG. 1 and the connector 40 shown in FIG. 2 is illustrated. As shown at reference numbers 60 and 62, when the MTP connector 20 is attempted to be engaged with connector 40, the ferrule surround portion 26 of the MTP connector 20 interferes with the internal geometry of the connector 40. Specifically, ferrule holder portions 64 and 66 interfere with connector geometry 68 and 70, respectively, to prevent proper engagement and ferrule-to-ferrule mating. Thus, the internal geometry of the conventional connector 40 prevents proper mating because a clearance is not provided for the surround structure of the MTP connector.
In order to solve the connector interference problem that occurs when mating a TIA FOCIS 5 MTP connector and an OptiTip connector, what is needed is a change in either connector structure that will permit engagement. Thus, it would be desirable to provide a connector having structure that allows the connector to mate with a connector having dissimilar structure. Further, it would be desirable to provide an adapter that allows for the mating of dissimilar connectors, for example, an adapter for mating a TIA FOCIS 5 compliant MTP connector with an OptiTip connector available from Corning Cable Systems of Hickory, N.C. A desirable adapter would provide proper connector maintenance and alignment while reducing or eliminating forces applied to connectors engaged with conventional adapters.